I. Field of the Invention
The present invention relates generally to internal combustion engines and, more particularly, to an improved rotary intake and exhaust valve construction utilizing a compressed fuel/air mixture as coolant, a lubricant, and to provide a gas bearing.
II. Description of the Prior Art
Conventional internal combustion engines include a housing with at least one piston member reciprocally mounted within a cylinder formed in the housing. Fuel intake passage means formed in the housing supply fuel to the cylinder for combustion while, similarly, the exhaust gases from the cylinder pass through exhaust passage means formed in the housing and to the engine exhaust system.
In order to permit the intake of fuel into the cylinder and the expulsion of exhaust gases from the cylinder at the desired engine cyles, an intake vavle and an exhaust valve are provided in the intake and exhaust passage means, respectively. These valves permit fluid flow or communication through their respective passage means upon opening and, conversely, when closed prohibit such fluid flow.
There are many different types of previously-known intake and exhaust valves. One type of previously-known valve member employs a circular closure plate with an axially attached elongated stem. The plate cooperates with a valve seat formed in the housing while a spring attached to the elongated stem normally urges the valve to its closed position. Conversely, opening of the valve is accomplished by depression of the valve stem by a cam, rocker arm, or other appropriate means. This simple type of engine valve, however, is disadvantageous due to its high cost which, in turn, results primarily from the multiplicity of components required for the valve and its actuation. Moreover, these previously known engine valve systems are both heavy and bulky in construction.
A rotary engine valve forms another previously known engine valve in which an elongated cylindrical valve member is rotatably mounted within the engine housing in the fuel intake or exhaust passage means for at least one, and preferably several, engine cylinders. Diametric throughbores are provided through the cylindrical valve member so that upon rotation in synchronism with the internal combustion engine, the valve members permit fluid flow through the intake or exhaust passage means via the diametric throughbore at preselected rotational positions of the valve member.
An improved rotary valve construction is disclosed in my earlier patent, U.S. Pat. No. 4,198,946 as having a valve with internal cooling and improved seals between the engine housing and the rotary valve. More specifically, each valve member of that reference includes at least one axial passageway which is fluidly connected at both ends to the fluid coolant system of the internal combustion engine so that a flow of coolant axially through both valve members is obtained.
Despite the advantages of rotary valves in general and U.S. Pat. No. 4,198,946 specifically, a more efficient and advantageous structure for cooling and lubricating is desirable which would eliminate the need for providing a flow of coolant through the valve members. By eliminating the flow-through of coolant, additional steps related to machining and construction can be eliminated.
Furthermore, the bearing construction of known rotary valves is very expensive and subject to considerable wear. Thus an improved bearing is desirable.